layer:
  id: "boundary"
  description: |
      Contains administrative boundaries as linestrings.
      Until z4 [Natural Earth data](http://www.naturalearthdata.com/downloads/) is used after which
      OSM boundaries ([`boundary=administrative`](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative))
      are present from z5 to z14 (also for maritime boundaries with `admin_level <= 2` at z4).
      OSM data contains several [`admin_level`](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative#admin_level)
      but for most styles it makes sense to just style `admin_level=2` and `admin_level=4`.
  fields:
    admin_level: |
        OSM [admin_level](http://wiki.openstreetmap.org/wiki/Tag:boundary%3Dadministrative#admin_level)
        indicating the level of importance of this boundary.
        The `admin_level` corresponds to the lowest `admin_level`
        the line participates in.
        At low zoom levels the Natural Earth boundaries are mapped to the equivalent admin levels.
    disputed:
      description: |
          Mark with `1` if the border is disputed.
      values: [0, 1]
    disputed_view:
      description: |
          Field containing name of the disputed area (extracted from border relation in OSM, without spaces) and ISO2 code of country, which wants to see the boundary line.
          For country boundaries only (`admin_level = 2`).
          Value examples from Asian OSM pbf extract
      values:
      - AbuMusaIsland_AE
      - BaraHotiiValleys_CN
      - ChineseClaim_CN
      - Crimea_RU
      - Crimea_UA
      - Demchok_CN
      - Dokdo_JP
      - IndianClaim-North_IN
      - IndianClaimwesternKashmir_IN
      - PakistaniClaim_PK
      - SamduValleys_CN
      - TirpaniValleys_CN
    maritime:
      description: |
          Mark with `1` if it is a maritime border.
      values: [0, 1]
  buffer_size: 4
  datasource:
    geometry_field: geometry
    query: (SELECT geometry, admin_level, disputed, disputed_view, maritime FROM layer_boundary(!bbox!, z(!scale_denominator!))) AS t
schema:
  - ./boundary.sql
datasources:
  - type: imposm3
    mapping_file: ./mapping.yaml